Question

【題目】脫式計(jì)算，能簡(jiǎn)算的要簡(jiǎn)算。

3.2×0.25×1.25 2.7×99

3.75×102 8.6×99+8.6

50-1.35-0.65 2.5×4.4

4.5×10.1 2.36×101—2.36

（1.25+0.25）×0.4 98×6.5

25×× ÷÷14

÷×9 63×÷．

Answer 1

【答案】

3.2×0.25×1.25

=（4×0.8）×0.25×1.25

=（4×0.25）×（0.8×1.25）

=1×1

=1

2.7×99

=2.7×（100-1）

=2.7×100-2.7×1

=270-2.7

=267.3

3.75×102

=3.75×（100+2）

=3.75×100+3.75×2

=375+7.5

=382.5

8.6×99+8.6

=8.6×（99+1）

=8.6×100

=860

50-1.35-0.65

=50-（1.35+0.65）

=50-2

=48

2.5×4.4

=2.5×（4+0.4）

=2.5×4+2.5×0.4

=10+1

=11

4.5×10.1

=4.5×（10+0.1）

=4.5×10+4.5×0.1

=45+0.45

=45.45

2.36×101—2.36

=2.36×（101-1）

=2.36×100

=236

（1.25+0.25）×0.4

=1.5×0.4

=0.6

98×6.5

=（100-2）×6.5

=100×6.5-2×6.5

=650-13

=637

25××

=25×（×）

=25×

=5

÷÷14

=÷（×14）

=÷4

=

÷×9

=×9

=42

63×÷

=28×

=44

【解析】略